Functions of Heat Pump Models Si01-40632 Functions and Control2.3 Fan Speed Control for Indoor UnitsControl Mode The air flow rate can be automatically controlled depending on the difference between the settemperature and the room temperature. This is done through phase control and Hall IC control.For more information about Hall IC, refer to troubleshooting for fan motor on page 90.Phase Steps Phase control and fan speed control contains 8 steps: LLL, LL, L, ML, M, MH, H and HH.= Within this range the air flow rate is automatically controlled when the FAN settingbutton is set to automatic.Note: 1. During powerful operation, fan operate H tap + 50 - 90 rpm.2. Fan stops during defrost operation.Air Flow RateControl forHeatingThe following drawing explains the principle for fan speed control for heating:Air Flow RateControl forCoolingThe following drawing explains the principle of fan speed control for cooling:Step Cooling Heating Dry modeLLL (Heating thermostat OFF)25 · 35kW class :500 - 860 rpm(During powerful operation :850 - 910 rpm)LL (Cooling thermostat OFF)LMLMMHHHH (Powerful)(R2818) (R2818)-1.5˚C-0.5˚C-1˚C-2˚CLMLMThermostatsettingtemperaturePhase controlDifference between roomand set temperaturefan speed (R2819)+1.5˚C+0.5˚C+2˚C+1˚CMMLLfan speedDifference between roomand set temperaturePhase controlThermostatsettingtemperature (R2820)
